I have the complete National Elevation Dataset from USGS in over 3000 ArcGrid files (coming to almost 190 GB), and a polygon shapefile of Colorado counties. I'm trying to use ArcMap Zonal Statistics to get the mean elevation for every county in Colorado, but after hours of processing, it repeatedly errors out. Is the mosaic just too big to work with?
I've tried Raster Calculator (to go from float to int) and Mosaic To New Raster, but both have failed.